


deep blue

by hellhoundsprey



Series: spn kink bingo 2020 [6]
Category: Supernatural
Genre: Alien Castiel (Supernatural), Alternate Universe - Science Fiction, Alternate Universe - Space, Alternate Universe - Witchcraft, Bathtub Sex, Body Horror, Bottom Sam Winchester, Bulge Kink, Cybernetics, M/M, Oviposition, PAH – porn & angst & horror, Past Character Death, Prosthesis, Tentacles, Top Castiel (Supernatural), Witch Sam Winchester, in a greater sense
Language: English
Status: Completed
Published: 2020-02-14
Updated: 2020-02-14
Packaged: 2021-02-22 14:33:35
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,848
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22717549
Author URL: https://archiveofourown.org/users/hellhoundsprey/pseuds/hellhoundsprey
Summary: Sam’s the first from his gene pool to make it past the draconian criteria of the Magick Crafts Society, and he’s fuckinghellbenton finishing his studies with an actual degree.2020 kink bingo square 15: bathtub sex
Relationships: Castiel/Sam Winchester
Series: spn kink bingo 2020 [6]
Series URL: https://archiveofourown.org/series/1602964
Comments: 30
Kudos: 89
Collections: SPN Kink Bingo 2020





	deep blue

**Author's Note:**

> Watch out for the NSFW-ish illustration down south.
> 
> Happy Valentine's ❤.

As he squints down the seemingly bottomless cave entrance, Sam considers if his father might have been right about this not being worth it.

He throws a helpless glance back at his beat-up ship. Took him months to get the coordinates, weeks to collect the supplies. He has just enough nutrition tabs to make it back home—overcalculated on the fuel. Not a failure per se, but the academy will find ways to retract that shit from his overall score.

His palm is damp inside his glove. Eyes back down to the prize.

His decade-old suit flutters tight around his skin. He can hear the Zhu-Liks banging against the walls of their glass containers, somewhere in the stuffed depths of his bag.

You could be a legend.

He allows himself one last deep, soul-hollowing sigh. Mutters, “Fuck it,” and begins his descent.

The planet is ridiculously small. Hidden well inside a tight ring of asteroids, nobody’s been insane enough to scour it for the vague promise of some old-ass fairytale. Yet.

Sam’s bloodline isn’t known for its heroes, for medals or achievements. Humans (that nobody bats an eye for anyway)—mostly mechanics, with an odd bounty hunter strewn in around every other generation or so.

Sam’s the first from his gene pool to make it past the draconian criteria of the Magick Crafts Society, and he’s fucking _hellbent_ on finishing his studies with an actual degree.

The past five years cost him ten years off his life, a leg, an arm and an eye and approximately twelve percent of his brain mass, but there’s barely a thing science can’t replace these days.

The night vision in his prosthesis activates once the light of this planet’s three moons loses its fight against the obvious odds. Sam moves at a careful pace, one foot in front of the other and his hand constantly on the wall for stabilization.

Sixty percent humidity and rising.

The drips and drops of water echo through the narrow tunnel. Sam spots a snail, then another.

And another.

Sam takes his hand off the progressively alive walls and keeps it that way.

Temperatures climb into the seventies. Eighties.

Sam blinks away sweat and balks at the info reflecting off of the inside of his helmet.

Oxygen? That can’t be right.

Sam shakes his head. “Keep it together.”

The ever-red bar in his vision turns green.

_Atmosphere: non-hazardous._

“What the…”

_“Atmosphere: non-hazardous. Oxygen supply: deactivated. Please take off your helmet. Please take off your helmet.”_

“No, shit, that’s not—shit, _shit_.”

_“Please take off your helmet. Please take off your helmet. Plea—”_

Sam grits, “Fucking piece of junk,” and grudgingly rams his finger into the flashing, now un-secured button.

The visor retracts instantly and confronts his face with the hot-damp climate. Sam’s eye burns and he swears while he rummages through his bag, finds the correct ointment, tilts his head back to drop it into his eye. He had applied it generously all over his skin and easily-reachable depth of all orifices, and this is probably just the sudden heat causing that discomfort and not any weird-ass poison or anything, but... Safety first.

He huffs, slightly out of breath. His lungs flutter securely and bewitched. Just his nerves getting the best of him. But who’d expect fucking breathable atmosphere? His professors are gonna love that. Sam takes a quick sample of both the gaseous environment and the wall liquid before he continues his descent.

The further down he goes, the less noise there is. Not much there to begin with; no fauna or flora to be seen on the surface. Last carbon you’d run into around these parts of the galaxy is several light-years away.

General folk avoid these death planes. Scientists and witches, though? Gold mines. Stuff of dreams, of power and prestige.

Sam’s brother had joked that if Sam would die on this mission, at least his ship could get tracked and they’d be in the lucky position to see what this place can do to a human corpse…unaware that, yes, Dean, you complete moron, that’s the fucking protocol. Ah, the luxury of ignorance.

You don’t go chasing ancient myths without signing a fucking living will.

Sam doesn’t mind the idea of death. It’d just be so very…inconvenient.

He still has so much left to do.

Miles from the surface, the soup-thick darkness begins to fade into light. Sam checks his prosthesis again, smacks it with his finger. The light won’t go away.

Close to a hundred degrees now, and the sweat pearls off Sam’s balmed skin.

A low humming sets in, so gently that Sam can’t pinpoint the exact time it started. Which will cost him another point or two. Sam huffs, keeps walking.

Echoes of splashes at 15:15:03. Distant, gentle—its volume increasing the deeper he goes. Sam steps into a puddle at exactly 15:26:56.

The snail population has vanished. Sam’s prosthesis lists the impressions his scent feeds him—earth, stone, ocean, algae.

Everything shines in a hue of blue-purple, of the bright reflections of—H2O?

Sam’s mind races with the possibilities of his findings so far. And he hasn’t even reached his destination yet.

“No visible source of light,” he murmurs, for the record. He’s shin-deep in the water now.

At 16:48:36, he hears, _“What are you?”_

Sam’s body freezes.

His mouth opens, ready to respond, “I come in peace. I was sent by the university of the Magick Crafts,” but the voice interrupts him as if he’d already said it all.

“ _A human? What is a human?”_

“We, uh. Mainly consume carbon-based sources of energy, t-to…”

_“Oh,”_ the voice says. _“How disappointing.”_

Sam hesitates. “Uh… sorry.”

_“Come forth,”_ he hears, _“let me see you.”_

Sam’s grateful that his prosthetic leg can’t be paralyzed by something as irrational as fear. He drags himself on, further down the cave. His heart rate won’t quite peak as he’d expect it, given the fact he’s—

_“What is a ‘God’? Oh,”_ they interrupt themselves. _“Really? How flattering.”_

Sam observes, “You’re a mind reader.” There’s nothing else to see yet but dripping walls, but water and light. The tunnel makes a turn half a mile down, maybe…

_“‘Mind’? ‘Reading’?”_

A considerable amount of water splashes.

_“I simply—know. Everything.”_

Sam mentally slaps himself for thinking of a snarky remark and mentally slaps himself _again_ for slapping himself mentally, before he gives up and sticks his artificial arm into his bag.

“I just came to—”

_“—talk. I haven’t talked in… Oh my.”_ It balks in settling realization. _“I never.”_

Just behind the turn, the tunnel opens to what must be miles and miles in depth and height of an underground lagoon. Light dances in its pure form, without insects or visible plants, and amid the opening lies a giant sea.

The being floats just by the shore, closest to the tunnel entrance, closest to Sam.

Mere feet divide them.

Sam only barely jumps backwards.

“I-I’m a, I just—”

_“How curious.”_ Dozens of eyes focus on him. _“I expected you to be…taller.”_

Deep in his bag, Sam’s cybergenetic hand tightens around the bundle of protective herbs. He takes a stabilizing breath before he takes another, seemingly impossible step.

“My name is Sam Winchester. I come in peace. I was sent here to scale this place to bring my magick studies forth. If you want me gone, I will do so, immediately. I do not intend to disturb you or—”

The being ‘smiles’. _“You already disturbed me.”_

“—o-or bring you… Look, can you stop interrupting m—”

_“Come forth, Sam Winchester. No, I do not care for your so-called ‘social norms’. Yes, come closer. I, too, have no intent on doing you any harm. Oh, how curious.”_

Sam forces himself to do as he’s told despite a mass of tentacles spilling out of the water and towards him.

_“How very curious,”_ the being not-says, and with that, Sam’s feet get swept from underneath him and his back hits the slippery floor.

The tentacles wrap around his feet and _pull_ , and he can’t even scream.

The being hefts itself out of the water, and for a death-screaming fragment of a second in which all of his life races past his eye, Sam sees nothing but purple-black, slick flesh.

He not-blinks his eye and there’s—

a face.

_“You are warm, Sam Winchester.”_

Humanoid face. Like, mouth and nose humanoid. Sam feels himself shaking in fear, his bladder casually releases while the tentacles hold him firm—but not too tight.

Like you’d hold a squirmy animal, careful so it shall not drop and hurt itself.

_“This. What is this?”_

“Ah, m-muh-my. I-it’s a, a prosthesis, m-made out, out o-of.”

The being puts its ‘mouth’ around Sam’s calf and bears down.

Sam blacks out for a second.

The creature is all up in his face at the next.

_“Here, too,”_ it says, focused on Sam’s artificial eye, and it smells like nothing Sam has ever known or heard of. It forgot to cover all its eyes with its illusion and Sam thinks he hears, _“You don’t mind them anyway, do you?”_ and he thinks, “Yeah, I don’t,” and, shit.

The sea of eyes shines bright in facets of white and blue. Every single one moves separately, takes in every inch of him.

That face shortly flickers through Dad, through Dean, his professor, his mom. Settles on Cas, out of all of them, and Sam’s dumb heart tenses.

How long has it been since the funeral? Eight years? Nine?

Brown-black hair, soaking wet like his pale, unharmed skin; the purple-spotted mucosal shines through when Sam doesn’t focus on it.

The few Zhu-Liks that weren’t crushed by either the now-shattered glass or Sam’s body break free, frantically. They piston into the air but the being snatches them, one by one (or all at once, Sam is too close to crane his neck right and fast enough).

Sam watches with growing panic how the moths try to escape. How some of them stick to the suckers or get crushed.

_“Oh. Apologies. Oh.”_

The being states, _“Fascinating,”_ as it finally gets a hold of the last one without killing it.

Poor thing looks as horrified as a bug possibly can, nervously twitching its legs, its now-damaged wings.

The being holds the insect up to its eyes. Sniffs at it. Slithers its tongues to gently tap it.

Both the Zhu-Lik and Sam don’t dare move a single atom of their bodies.

Finally—and Sam kinda feels like breaking into tears—, the Zhu-Lik is set free.

Him and the being both watch it hurrying off into the wide-open of the cave.

_“Do you have any more?”_

Sam almost-shakes his head.

_“What else did you bring? Are these for me?”_

The tentacles retract their hold on Sam to go for his duffle instead. “Uh, n-not, n-not really, uh…”

_“Most curious. Oh, very, very curious.”_

Sam watches his supplies clink-clanking to the stone floor, how every item gets carefully picked up and inspected.

Sam not-hears: What are these? Where did you get these?

He replies, “From various planets. There’s several galaxies out there. Uh, well, I dunno if it makes sense since you… Uhh. Oh. I see. Okay.”

Listen, look—he _was_ prepared for mind tricks, for illusions, bends in time and space. So easy to pick a familiar face from Sam’s memory, create a mirage, make him pliable.

But…Cas.

He’s been in therapy for that shit, for God’s sake.

This isn’t Cas, of course, but it looks _just like him_ —back when he still was in one piece, and maybe that’s somehow worse. Because he’s _alive_ and _well_ and _right there_ with that adorable, confused frown of his upon being faced with Sam’s odd tools and spells and supplies.

But it’s not him. You know he’s dead. You and Dean helped to cremate his remains.

A handful of the creature’s eyes swipe towards Sam while the rest keeps dancing over the colorful loot. _“What is ‘Cas’?”_

“Uhm.” Sam clears his throat. His voice breaks at the thought of his test score. “It’s just, uh, someone? From my past. You’re wearing his…face. Right now. Anyway, uh—”

Sam sits a little straighter, considers getting up. But they’re at eye level now and maybe that’s best for a friendly conversation, y’know, human to light-century-old mythical creature.

He clears his throat, again. Slicks his already-drippy hair back over his head, out of his face. “Reason I came here is—”

_“What is ‘magick’? … Hm. I see.”_

“Yeah, uh, anyway, uhm.”

_“There are…stories about me?”_

The being’s eyes flicker, point towards nothing. Through Sam, through the thick shell of this planet, light-years’ worth of travel and time.

_“I did…”_ It hesitates. _“Not know.”_

“You’ve been here all your life?” Sam’s heart picks up. “You—you never left this cave?”

The being transmits, _“Yes. No,”_ and slips its body further back into the water.

“Why’d, uhm—why?”

_“This is my home,”_ it argues. Flecks of light dance across its skin, the shallow waves. Cas’ face blends less and less into its actual, feature-less self. Several ‘eyes’ jump along the questioning line of Sam’s body. _“You have travelled many worlds. I see them all.”_

“In my…?”

_“Yes. And outside of it.”_

“So you see…everything?”

The being blinks Cas’ eyes. _“I forgot.”_

Sam’s hand is wrapped around the cliff. The H2O is warm enough to waft soft steam up into his face. He asks, trembling, “Forgot what?” and the being says,

_“I slept.”_

It submerges itself entirely.

Sam almost falls into the water with how frantically, how instinctively he surges forward to grab Cas.

From underwater (no, inside your head), Sam hears, _“You woke me.”_

“I—I’m terribly sorry.”

_“‘Sorry’.”_ A hum. _“What a beautiful word.”_

Desperation grows, fast. “What are you?”

_“Do the tales not say, Sam Winchester?”_

“Th-they’re just—fairytales.”

A low hum. Like mountains emerging from the ground. A new world being born, somewhere.

_“I don’t see a word for what I am,”_ Sam hears. _“Not in your head. Not anywhere.”_

Sam polite-smiles, “Ah,” and his student-heart bolts with both the ecstasy and complete panic of having run into…this.

His human nature shrivels in compassion, though.

Once his findings get published, scientists will—

_“I do not fear them.”_

Oh.

_“I am sorry that you were under the impression that you were able to find me simply due to your skills, Sam Winchester.”_

You knew I was coming.

_“Yes.”_

You wanted me to find you.

_“Yes.”_

“But…”

Sam’s voice fails him. This is not the kind of attention he’s ever wanted to attract. Didn’t know someone…something…a _god_ …even knew he existed.

He clutches his artificial shoulder while his face derails in a sea of confusion.

“But—why?”

Cas’ head breaks the surface, slowly, unblinking. Two eyes only, just like Sam’s never-recovered heart remembers: strikingly blue and gentle.

There are no waves in the water.

Cas’ mouth smiles. _“I began to…feel.”_

“F…feel?”

_“Yes.”_

“W-what did you… _feel_?”

_“‘Loneliness’.”_ The creature floats back to shore, to Sam. _“‘Boredom.’”_

Sam’s shaking. He should have eaten extra, earlier. “Th-that’s, uhm—I’m sorry to hear that.”

_“No,”_ it not-says, close enough to touch. _“It is beautiful.”_

“Your first emotions should be, I dunno—happier?”

_“‘Happy’?”_

Tentacles slip onto the cliff, pull the being further up. Two humanoid arms, humanoid torso. Scars appear where Sam remembers them, once he remembers them. Cas’ tattoos.

_“What is ‘happy’?”_

Cas’ hand reaches for Sam’s cheek, and it’s already too late when Sam realizes he probably, absolutely, definitely _shouldn’t_ —

—lean into the touch.

Cas’ face is too close. Sam’s eye fills with tears.

The creature blinks, gaze strictly on Sam’s face. The tremble of his lip.

It says, after a fast-forward through Sam’s brain, _“I see.”_

The creature presses Cas’ mouth onto Sam’s.

The emotional recoil nearly throws Sam back onto the ground. He yells, “Woah!” and his biological hand pushes on Cas’ chest to keep the creature away. He feels a new layer of heat bubbling into his face and simultaneously drains of all color, and it all happens so fucking fast he swears he can _feel_ the whiplash.

Or that’s just the sensation of lost gravity due to being grabbed by a dozen fucking huge tentacles.

With his body mere inches off the ground, Sam Winchester’s stomach decides that it’s had enough. He vomits—mostly water and stomach acid.

The creature puts Cas’ hands on Sam’s face, almost nose to nose again and Sam pants, “You’re not him, y-you’re _not_ him,” and the creature cocks Cas’ head again.

_“Apologies. Does this upset you?”_

Dean’s face says, _“Is this better?”_

Sam splutters, “N-no, no.”

Mom frowns, worried. _“This?”_

Sam can’t kick his prothesis. Can’t move his arm or reach his tools, strewn all over the ground mere feet away. “J-just, fuck—stay him, okay, stay HIM!”

The tips of Cas’ fingers map out the shape of his face. Slip along the scruff on his chin, his sideburns, into his hairline.

Sam forces his eyes closed, his spirit calm.

You’re hyperventilating. Easy. In…and out…in…and out…

_“You are scared.”_

A teeth-gritted, “Yes.” Gentle-rough fingers along the rabbit-kicks of his carotid; the worst kind of goosebumps.

_“Why?”_

Cas’ hands are both on his clothed chest, but one of the tentacles finds the zipper-activating button on accident. Warm air hits Sam’s upper back, and his panic finds a new high.

“Nonono, _wait_ , uh, wait—”

_“I told you: I mean no harm. What is this?”_

“I need it,” chokes Sam—the tentacles pull his spacesuit from him, undress him carelessly, easily. “P-please, careful with that, I, I need it to get back!”

_“How curious.”_ The creature holds the limp fabric to Cas’ face. Sniffs it—frowns—gently lowers it to the floor. _“Are all humans this…fragile?”_

“I— _hey_. Yeah, we—need oxygen, and o-our skin is an organ with a, a strictly balanced—c-can you _please_ stop _touching_ me, please?”

The creature hums, _“‘Oxygen’,”_ its tentacles and Cas’ hands running along Sam’s oily, sweaty skin. Exploring, tickling in their oblivion. _“Hm. You…smell.”_

Sam grunts. “Well, you don’t exactly run into a goddamn bathtub around these parts of the galaxy.”

The creature wipes Cas’ fingers across Sam’s bare chest, rubs them together in front of his face. He helps himself from Sam’s mind to try out the words, _“‘Xctechlop.’ ‘Almond.’ ‘Rosemary.’”_

“Protection.”

Cas’ face is littered with eyes that disappear upon the creature looking at Sam in wonder.

“F-from the. Atmosphere. It’s a protective ointment.”

The creature puts Cas’ oily fingers into Cas’ mouth to suck on them.

Once satisfied, it smacks Cas’ lips.

_“Fascinating.”_

Another kiss and Sam scrunches his face, tries to fight, but he can’t move an inch. He’s let up and hisses, “Stop _doing_ that,” and feels something wet and warm flicking at his chin, the corner of his mouth next.

Oh, God.

The creature slips one of its tongues behind the too-late seal of Sam’s lips.

But you like this—‘kissing’—don’t you?

Sam garbles out loud what’s supposed to mean, “Uh, _no_ ,” but the being has already read his mind.

You ‘kissed’ him a lot. ‘Cas’.

… Yes.

His physical shell disintegrated. You have not kissed him since.

C-can we… _not_ talk about…?

_“Of course,”_ it not-says, and presses their lips together. Sam is so relieved he forgets his current predicament and pushes his own tongue into the game.

The change is immediate.

Sam’s own pleasure-sigh slaps him right back into reality.

He splutters. The being lets up, looks down at him, puzzled.

It pulls him into the lake with it. The H2O gushes warm and almost… _comforting_ around them. Sam’s never seen so much of it in one place.

Sam blabbers, “Please don’t hurt me, please—I just wanna get back home, this is just a stupid mission an’ my brother’s gonna lose his _mind_ if I go missing and—”

Cas’ mouth kisses him again. Soothing, with growing finesse.

Sam’s body submerges into the warm waves and goes a little limper with it.

The being tongue-fucks his mouth, generously supplied by Sam’s memory, and his eyes slip closed. Cradled close and God, he swears he can smell— _Cas_. The herbs he used to smoke all the time. The salt and grime of his skin.

_“You too are lonely, Sam Winchester,”_ the being notes, and Sam swallows his pride and copious amounts of alien-spit while they nose past his ear, slip their tongues around and behind and across—his face, the grimy line of his neck.

Sam shiver-moans, pressed too-close and weightless in the being’s grip—suspended by countless tentacles of all sizes and water licking up at him from the movement. Again, Cas’ hands get a hold of his face for a kiss, slips its tongues past his teeth and he’d splutter around the sudden surge of it, the insistent pressure, if there was any space.

Sam’s got just enough time to think ‘uh, wait, this is different’ before he chokes.

They map him out. His entire system screams WRONG upon the tongues slipping down his esophagus, peek into his too-empty stomach; slip back up, into his nose, his trachea.

_“Warm,”_ comments the being. _“Here, too.”_

A slick arm rolls up against Sam’s ass crack, from tailbone up his taint and nudging his balls aside to flip up his cock, before it slithers back down, gets another tentacle to join in.

Shit, no, g-god, that’s uh, _god_ —does it know this is for…?

_“Oh, is it?”_ the being replies, and Sam rushes, “N-not like, uh,” but he’s getting his ass spread already and one of the thinner tentacles emerges from the water to push its way inside him with alarming speed.

And lack of manners.

“Shit, shit, wait, ah—”

Another tentacle found his urethra now and starts its descent. The other is pushing past depths of his colon Sam didn’t know he could _feel_.

Cas’ voice hums, _“Fascinating.”_

Sam’s mouth hangs open.

His body reacts to the unfamiliar (and these days way too rare) intrusion in the only way it’s ever learned how:

His cock begins to chub up.

_“Oh,”_ the being says, _“how convenient. I have always wanted to try this.”_

“Try what. Try _what_?”

_“There should be enough space. Ah, yes.”_ Another, way bigger tentacle pushes past Sam’s sphincter. He cries out. _“This is acceptable. Excellent.”_

Sam babbles, “What’re you doing,” and gets another kiss, gets his tongue sucked while the creature fucks into his cock until it’s fat and throbbing.

If they take any points off of him for _that_ , then, honestly, what the fuck.

_“I have one just like that,”_ Sam hears, and feels the press of something—

worryingly warm and slick.

The half-mile-long probe retracts from the depths of his bowels and Sam has just enough time to stutter a syllable or two before the creature replaces it with his clearly not-humanoid, not-anything Sam’s ever anticipated near his nether regions mating tentacle.

The rigged head bumps into every nerve it passes, and it’s followed by an endless supply of… _more_.

There should be pain where there isn’t, but Sam’s crying with generally being overwhelmed.

His stomach begins to bulge out with the sheer volume of cock he’s getting stuffed full with.

“God,” he whines, his hands magically free to grabble at the creatures (Cas’) face, hair, neck, “p-please, I’m, y-you c-can’t…”

A hot gush of liquid empties somewhere deep inside of him, and it feels—wrong.

Except that it doesn’t.

_“Do not worry,”_ the creature lap-speaks into Sam’s tongue. _“This will not harm you.”_

Sudden pressure builds and breaks, too fast to comprehend until it’s already done, and Sam’s body contracts _hard_ around the ungiving shape of a huge, round object.

The object travels further, and further, and Sam’s brain flails to the horrible conclusion: egg.

There’s an egg going up that thing’s cock and it’s gonna plant it right inside of him.

Sam manages a high-pitched, “Uhm, _uh_ ,” before another one pops past the tight suck of his asshole to follow behind the first.

Something in him short-circuits.

He’s been through some shit, did some kinky stuff, but this is those two categories meeting on the completely wrong ends. Alas, there’s nothing he can do.

‘Cas’ licks into his mouth, purr-vibrating low, and Sam shivers. Painfully aware of his own cock—forgotten and hopelessly hard, dripping with his own and the creature’s slick. Gets kissed and for a moment it’s exactly like _kissing Cas_ , that hunger and love and pressure and _never letting you go_.

The first egg spills out of the solidly rigged head of the creature’s cock, nestles all nice in a fresh glop of come or slick or whatever it is that’s so warm and gooey in him—and the cock retracts a few inches, already bulges with the next egg.

Sam hiccups, “Oh,” and the creature doesn’t have anything to add to that, apparently.

They’re kissing through it all because that’s nice, that’s something Sam is used to. Tongue and spit and he’s light-headed, his non-artificial fingers shaky and the skin on his stomach stretches painfully. He groans, looks down in-synch with the creature.

His stomach is expanding rapidly. The eggs visibly push against each other inside of him, desperate for space.

The creature vomits a generous amount of slick between their bodies and uses his Cas-hands to rub it into the hard swell of Sam’s belly.

They rub hard enough that Sam can feel how thinly stretched he is already, hard enough to nudge the eggs around and he whines, powerlessly, as he comes.

His insides rhythm-suck at the creature’s cock and it hums, pleased, while Sam’s spilling in rivulets between their bodies. He’s bound so tight he can’t even writhe, just fish-gasps and clenches around the eggs, the creature’s cock still pumping inside of him.

_“Pleasant,”_ the being decides. It’s apparently empty now and humps the available twenty inches or so in front of the eggs that it’s got left. That perfect, bulbous head rubs at Sam’s insides just right and he moans, completely out of his mind with the stimulation and horror. The creature takes that as an incentive to stuff his mouth with his tongues again, snaps his Cas-hips to fuck Sam in a horribly…humanoid fashion.

“Don’t stop,” he gasps, “don’t fucking stop.”

The ridges of the creature’s mating tentacle catch on his over-sensitive hole on every oblivious stroke. Only reason he’s not getting pulled inside-out is the generous amount of slick audibly smacking between their bodies.

  
[ ](https://hellhoundsprey.tumblr.com/post/190744037583/hello-yes-i-love-my-space-babies-hellhoundsprey)

Sam’s got Cas’ face tight between his hands, forehead to forehead. He cries, “I love you so m-much,” and comes again, harder this time, like a ship hitting him full speed.

His scream echoes off the walls.

It doesn’t stop. Not until he’s sobbing softly, and the creature cradles him. That cursed cock finally retracts from his now blown-out hole and is followed by a gush of slick that he swears he can _taste_ , and his eyes are closed but the creature keeps pressing gentle, wet kisses all over his face.

_“Sleep,”_ comes a thought, and just like that, Sam Winchester slips right into blissed, utter unconsciousness.

~

He wakes. In-suit, his bag right next to him.

His memories stumble after him and his body surges into a seated position; painful gasp, locking muscles, cold sweat.

His hands slap onto his stomach.

There’s…nothing.

He stares down at himself—his empty hands, his ever-flat stomach. Has a premonition to turn around, and there’s Cas, and Sam almost collapses right back into darkness.

“Shit!” he yells, “What the fuck!”

He grabs his bag. Cas doesn’t move, just observes. He’s completely dry, stark naked. Sam’s gone insane. You’re gone insane.

He sniffles. “How long was I out?” His voice feels off, not-his-own.

The creature says, “Just a few hours.”

Sam’s cyber eye spells a date he doesn’t think he…remembers.

When had he arrived here?

Sam’s eye swims. He blinks. There’s no breath in him.

“I. I have to go.”

“Of course,” nods the creature. “I will accompany you.”

“You—no.”

Sam gets to his feet, shoulders his bag; turns towards the creature but his feet begin to walk towards the cave exit. He raises his prosthetic arm and his eyebrows in a desperate threat.

“No, you—you stay here. Stay where you are!”

Cas takes a step towards him.

“I said—”

Cas has his arms behind his back. Wears that dumb, innocent face he’d use when he’d want something from Sam he didn’t know how to address. Didn’t know himself what that’d be, exactly, but knew he _wanted_.

“—I said _don’t_.”

Mere steps separate the two of them from the turn into darkness, back into the tunnel ultimately leading towards the surface. To Sam’s ship. The endless courses of the universe.

Behind the being, the lake is gentle. Glows—eternally, peacefully.

Cas’ lips pull into a most timid smile.

Sometimes, Sam wishes he couldn’t remember. That none of it ever happened. That they never met.

It would be easier.

The creature says, “I have decided.”

**Author's Note:**

> Keep your eyes peeled for these lovebirds, because there will be so much more to read about them...soon.


End file.
